Margaret Gelling, who has died aged 84, was for more than 50 years one of Britain's leading experts in the study of place-names; she was also highly successful in making that scholarship available to a very wide lay readership. Her election as a Fellow of the British Academy in 1998 - a source of great joy and pride - was a rare achievement for a scholar who bestrode her discipline, but had never held an academic post in any university.

Born Margaret Joy Midgley, she came from a Manchester family, but received her secondary schooling in Chislehurst, Kent, before achieving a wartime honours degree in English language and literature at St Hilda's College, Oxford, in 1945, where Dorothy Whitelock steered her linguistic interests towards place-name study. After a year (1945-46) as a temporary civil servant in London, she found more congenial employment for some eight years in Cambridge as a research assistant of the English Place-Name Society, when the society's base had been moved there from Reading.

In Cambridge she began the work on the names of Oxfordshire and Berkshire which was to lead to the publication of two volumes of The Place-Names of Oxfordshire (1953-54), building on the materials that had been initially collected in Reading by Sir Frank and Lady (Doris) Stenton. Here, Margaret broke new ground not only by presenting a much stronger geological and archaeological background to the names than was to be found in the society's previous county surveys, but also in investigating the field-names and minor names of each parish much more fully.

Margaret was indeed already involving members of local communities in the task of gathering evidence of these names and of local pronunciations. In 1957 she completed a PhD thesis (supervised by Professor Hugh Smith) on The Place-Names of West Berkshire for the University of London.

In Cambridge, Margaret had met and, in 1952, married the young archaeologist Peter Gelling, who came from the Isle of Man and possessed a polymathic range of interests and enthusiasms. When Peter was appointed as a lecturer in archaeology in the University of Birmingham, he and Margaret set up their home in Harborne, where she was to live for the rest of her life. That gave her access to a good library and a convenient central location for her place-name studies. In Harborne she became an active member of the local Labour party and created a beautiful garden; there Peter grew the vegetables, which she turned into a constant supply of good food for him and for all visitors to the house. She and Peter had no children of their own, but brought up her nephew, Adrian Midgley, from the age of six.

Margaret joined Peter's excavations in Dorset, the Isle of Man and in Cyprus, and travelled with him to Peru investigating the history of potato use and becoming adept at cooking at altitude

in a cave on a fire of llama dung. Her role came particularly to the fore on Peter's training excavations for Birmingham students for many seasons at Deerness, Orkney; for Margaret was in charge of the excavation's camp and responsible for the provision of basic and sustaining food. Generations of Birmingham archaeologists have the warmest memories of the good morale she helped to create.

The 1960s saw Margaret publishing innovative studies of particular place-names: those denoting pagan Anglo-Saxon gods and shrines; those incorporating the element -hamm ("enclosed meadow"); the survival of the Latin settlement term "uicus" in English place-names using the compound "wicham"; and the woodland terms found in the Birmingham region. They also saw her undertaking a huge amount of extramural and evening lecturing to groups throughout the Midlands, mostly under the aegis of the University's Department of Extra-Mural Studies (and its successors).

Her three volumes on the Place-Names of Berkshire (1973, 1974 and 1976) consolidated her scholarly reputation and in volume III she broke new ground by mapping detailed interpretations of the boundary clauses of Anglo-Saxon royal diplomas from the archives of Abingdon Abbey. But the volume that put her in an elevated position among English toponymists was her Signposts to the Past: Place-Names and the History of England (1978), which set out the transformation that contemporary scholars had wrought in place-name studies and showed us all how we might now understand and interpret the names of our own home areas. It became a fundamental handbook of up-to-date scholarship for all budding geographers, archaeologists and historians. Second (1986) and third (1997) editions met the continuing demand, and the volume is still in print.

From the 1980s and particularly after her husband's death in 1983, Margaret began to play a greater role within the University of Birmingham, whose traditions of "history from below" suited her political views. She introduced first-year historians to the study of place-names and supervised third-year archaeologists writing "parish studies" of the archaeology, place-names and settlement history of their own home territory. On the basis of Margaret's growing academic reputation and of the success of Signposts to the Past, other commissions followed.

Her Early Charters of the Thames Valley (1979) completed a series that had been initiated for local historians by Herbert Finberg; and her West Midlands in the Early Middle Ages (1992) provided a toponymist's insights into the settlement history of her home region. She served as president of the English Place-Name Society from 1986 until 1998; as Vice-President of the International Society for Onomastic Sciences from 1993 to 1999; and she was appointed OBE in 1995.

But in these years she was also preparing a further revolution in place-name scholarship. Since the foundation of the English Place-Name Society in the 1920s, the attention of scholars had been focused on "habitative" names that denoted settlements, which were thought to be earlier and more interesting than other place-names.

As a result of her studies with local groups and audiences, Margaret had become increasingly dissatisfied with this focus. In her Place-Names in the Landscape (1984) and then in revised form with the geographer, Ann Cole, in The Landscape of Place-Names (2000), she focused instead upon the topographical names, seeking to show that when they used particular words for a hill or a valley, the Anglo-Saxons were giving precise descriptions of the land-form that they saw, which we can still detect in the English landscape.

Up until her final illness Margaret continued lecturing to local audiences, to conferences and symposia, whenever she was invited. Extramural groups in Shropshire, whom she had first taught in 1959, became her research field-troops, providing much of the evidence for her five published volumes of the Place Names of Shropshire (1990, 1995, 2001, 2004 and 2006). Volume VI is at proof stage and she was working every day on VII until illness recently prevented that.

In devoting her life to adult education Gelling transformed our understanding of the development of the English countryside and of its nomenclature. Her plain-speaking and warm friendship will be much missed by all who knew her.